Nuprl Lemma : face-zero-and-one

∀[X:j⊢]. ∀[z:{X ⊢ _:𝕀}].  (((z=0) ∧ (z=1)) = 0(𝔽) ∈ {X ⊢ _:𝔽})


Proof




Definitions occuring in Statement :  face-zero: (i=0),  face-one: (i=1),  face-and: (a ∧ b),  face-0: 0(𝔽),  face-type: 𝔽,  interval-type: 𝕀,  cubical-term: {X ⊢ _:A},  cubical_set: CubicalSet,  uall: ∀[x:A]. B[x],  equal: s = t ∈ T
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  squash: ↓T,  true: True,  subtype_rel: A ⊆r B,  uimplies: b supposing a,  guard: {T},  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  implies: P ⇒ Q
Lemmas referenced :  equal_wf,  cubical-term_wf,  face-type_wf,  face-and-com,  face-zero_wf,  face-one_wf,  face-0_wf,  iff_weakening_equal,  face-one-and-zero,  interval-type_wf,  cubical_set_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  applyEquality,  thin,  instantiate,  lambdaEquality_alt,  sqequalHypSubstitution,  imageElimination,  extract_by_obid,  isectElimination,  because_Cache,  hypothesis,  hypothesisEquality,  natural_numberEquality,  sqequalRule,  imageMemberEquality,  baseClosed,  equalityTransitivity,  equalitySymmetry,  independent_isectElimination,  productElimination,  independent_functionElimination,  universeIsType,  isect_memberEquality_alt,  axiomEquality,  isectIsTypeImplies,  inhabitedIsType

Latex:
\mforall{}[X:j\mvdash{}].  \mforall{}[z:\{X  \mvdash{}  \_:\mBbbI{}\}].    (((z=0)  \mwedge{}  (z=1))  =  0(\mBbbF{}))



Date html generated: 2020_05_20-PM-02_43_24
Last ObjectModification: 2020_04_04-PM-04_57_39

Theory : cubical!type!theory


Home Index